Takafumi Matsumaru

Prof. Takafumi Matsumaru

Grad Sch of Information, Production and Systems, Waseda University, Tokyo, Japan
orcid
Professor. Waseda University, Japan

Research Focus & Metrics

Academic Career Length

33Years (1994-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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19 November 2002
Verified
Conference Paper
Closed access
Takafumi MatsumaruTakafumi Matsumaru
Takafumi Matsumaru
The Toshiba Modular Manipulator System, TOMMS, consists of joint modules, link modules, and a control unit with a joystick. A manipulator with 3-DOF is assembled using three joint modules and optional link modules into any desired configuration and shape, for example, a horizontal type and vertical type. The assembled manipulator is connected to the control unit, and the position of the end tip of the manipulator is controlled using the joystick without special handling. There is only one kind of joint module and link module. There are three input ports and two output ports on the joint module. The distance between the fore side and the back side of the link module is adjustable. The Jacobian matrix is applied to the control software. Control experiments were carried out and the efficiency of the design concept for mechanical hardware and control software was confirmed.

1 September 2006
Verified
Conference Paper
Closed access
Takafumi MatsumaruTakafumi Matsumaru
Takafumi Matsumaru
This paper discusses the mobile robot PMR-5 with the preliminary-announcement and display function which indicates the forthcoming operations to the people near the robot by using a projector. The projector is set on a mobile robot and a 2D frame is projected on a running surface. In the frame, not only the scheduled course but also the states of operation can be clearly announced as the information about movement. We examine the presentation of the states of operation such as stop or going back including the time information of the scheduled course on the developed robot. Scheduled course is expressed as the arrows considering the intelligibility at sight. Arrow expresses the direction of motion directly and the length of arrow can announce the speed of motion. Operation until 3-second-later is indicated and three arrows classified by color for each second are connected and displayed so these might show the changing of speed during 3-second period. The sign for spot revolution and the characters for stop and going back are also displayed. We exhibited the robot and about 200 visitors did the questionnaire evaluation. The average of 5-stage evaluation is 3.9 points and 4.5 points for the direction of motion and the speed of motion respectively. So we obtained the evaluation that it is intelligible in general

13 October 2022 in Sensors
Verified
Journal Article
Open access
PDF file
LSLi Shengyin
Li Shengyin
VDVibekananda Dutta
Vibekananda Dutta
XHXin HE
Xin HE
Takafumi MatsumaruTakafumi Matsumaru
Takafumi Matsumaru
Recently, the dangers associated with face generation technology have been attracting much attention in image processing and forensic science. The current face anti-spoofing methods based on Generative Adversarial Networks (GANs) suffer from defects such as overfitting and generalization problems. This paper proposes a new generation method using a one-class classification model to judge the authenticity of facial images for the purpose of realizing a method to generate a model that is as compatible as possible with other datasets and new data, rather than strongly depending on the dataset used for training. The method proposed in this paper has the following features: (a) we adopted various filter enhancement methods as basic pseudo-image generation methods for data enhancement; (b) an improved Multi-Channel Convolutional Neural Network (MCCNN) was adopted as the main network, making it possible to accept multiple preprocessed data individually, obtain feature maps, and extract attention maps; (c) as a first ingenuity in training the main network, we augmented the data using weakly supervised learning methods to add attention cropping and dropping to the data; (d) as a second ingenuity in training the main network, we trained it in two steps. In the first step, we used a binary classification loss function to ensure that known fake facial features generated by known GAN networks were filtered out. In the second step, we used a one-class classification loss function to deal with the various types of GAN networks or unknown fake face generation methods. We compared our proposed method with four recent methods. Our experiments demonstrate that the proposed method improves cross-domain detection efficiency while maintaining source-domain accuracy. These studies show one possible direction for improving the correct answer rate in judging facial image authenticity, thereby making a great contribution both academically and practically.

1 March 2005 in Autonomous Robots
Verified
Journal Article
Closed access
PDF file
Takafumi MatsumaruTakafumi Matsumaru
Takafumi Matsumaru
KIKazuya Iwase
Kazuya Iwase
KAKyouhei Akiyama
Kyouhei Akiyama
TKTakashi Kusada
Takashi Kusada
TITomotaka Ito
Tomotaka Ito

1 October 2006
Verified
Conference Paper
Closed access
Takafumi MatsumaruTakafumi Matsumaru
Takafumi Matsumaru
TKTakashi Kusada
Takashi Kusada
KIKazuya Iwase
Kazuya Iwase
This paper discusses the design and the basic characteristic of the mobile robot PMR-1 with the preliminary-announcement and display function of the forthcoming operation (the direction of motion and the speed of motion) to the people around the robot by drawing a scheduled course on a running surface using light-ray. The laser pointer is used as a light source and the light from the laser pointer is reflected in a mirror. The light-ray is projected on a running surface and a scheduled course is drawn by rotating the reflector around the pan and the tilt axes. The preliminary-announcement and display unit of the developed mobile robot can indicate the operation until 3-second-later preliminarily, so the robot moves drawing the scheduled course from the present to 3-second-later. The experiment on coordination between the preliminary-announcement and the movement has been carried out, and we confirmed the correspondence of the announced course with the robot trajectory both in the case that the movement path is given beforehand and in the case that the robot is operated with manual input from a joystick in real-time. So we have validated the coordination algorithm between the preliminary-announcement and the real movement

16 November 2009 in The Open Automation and Control Systems Journal
Verified
Journal Article
Closed access
Takafumi MatsumaruTakafumi Matsumaru
Takafumi Matsumaru
KAKosuke Akai
Kosuke Akai